If you can find a dispenser that changes their filters regularly then it should be ok.
I have been told boiling the water is not ideal due to the high iron-content of the water. However I have done this many times before and no issue.
I bought a stand-alone water filter (Japanese model ~8K thb) from HomePro that attaches to your kitchen sink tap. Have been using it for about a month now and no problem.
I think I spotted one dispenser on Soi-94 that have mounted the filter system externally so you can see that the filters are at least in operation.
Cheers,
GN.

Depends on the machine. The signs on their fronts all make the same claims.

I had no problem with the one in neighbor's apartment building until the water began smelling funny. Stopped using it and tried one in an apartment building mostly occupied by Thais. I was mostly well after drinking that water, so I switched to store bought water until the neighbor's stopped smelling. Then our landlady put in a machine with a BIG filter outside the water machine. When the filter is cleaned, you wouldn't believe how black the water coming out was. Anyway, out landlady's tests show the water going into our machine is cleaner than what comes out of the neighbor's machine.

I wouldn't bother with them TBH man due to most being sub-par like the other poster said. Item maintenance is still something that hasn't really filtered down to people here at the normal/general level of most things. Take cars, preventive maintenance is a very abstract thought to most locals.

How would you know for sure if they change the filters regular style etc? There is none.

Most of these machines just take the normal water which can be full of limescale and iron etc. I stick with stuff you buy from a mall, 7-11 or Tesco.....must be at least slightly more confidence in them than the run-of-the-mill water dispencer on the street, even if it's cheaper on the street. There certainly isn't anyone inspecting them (street water machines) or giving a shit about the machine unless it totally stops working. Same with most other stuff here....fix it when it breaks and not until (Who cares about anything sort of stuff?).

Don't read beauty magazines...they will only make you feel ugly - Baz Lerman

I'm really not sure why anyone would consider using them. My stepdaughter, whilst studying for her degree in food technology did a controlled test on a sample of these units in Bangkok. Her research was very detailed and wordy but the conclusion was that you would be safer filtering your tap water through an old tramp's sock.

These units for the most part are poorly maintained and appear to have everlasting filters.
They are breeding grounds for bacteria.

Is bottled water so difficult to get in HH or a home system so expensive? At least with a home system you have no one to blame if it's not well maintained.

"'The two most important days in your life are the day you are born and the day you find out why." - Mark Twain

Not really sure, they are filled locally by who? The seals are always taped. In BKK I always buy water this way from Sprinkle but they don't serve HH and I have never found a sealed bottle wher me the producer was known!

I personally have avoided them because of the unknown. Perhaps others have had experience or know shops where the source is known and known to be good.

"'The two most important days in your life are the day you are born and the day you find out why." - Mark Twain

There was a water processing "factory" in Soi 6, that is the proper Soi 6, not where the imposters live.

It is still there but has been closed for awhile. I had a look through at one time and they had all stainless steel equipment, big filters and a large UV unit on the end of the filling line. I have no idea why they closed, but the water was good.

May you be in heaven half an hour before the devil know`s you`re dead!

The best thing I did was to buy my neighbors water making machine before he moved back to America. It takes moisture out of the air then filters plus UV treats and dispenses it cold or room temperature. Our reverse osmosis hasn't been used since the water tastes great and never runs out even with a family of 5. Plus it dehumidify s there room keeping it feeling cooler.